Info on Erdos number project

"Most practicing mathematicians are familiar with the definition of one’s Erdös number [that is actually a long Hungarian umlaut over the “o” but we will represent it here by the ordinary two-dot umlaut widely available in html, since the true Hungarian umlaut isn't visible in some browswers — here is what it looks like if your browser supports it: Erdős.]. Paul Erdös (1913–1996), the widely-traveled and incredibly prolific Hungarian mathematician of the highest caliber, wrote hundreds of mathematical research papers in many different areas, many in collaboration with others. His Erdös number is 0. Erdös’s co-authors have Erdös number 1. People other than Erdös who have written a joint paper with someone with Erdös number 1 but not with Erdös have Erdös number 2, and so on. If there is no chain of co-authorships connecting someone with Erdös, then that person’s Erdös number is said to be infinite."